U.S. patent application number 14/570394 was filed with the patent office on 2015-06-25 for material for organic electroluminescence device and organic electroluminescence device using the same.
The applicant listed for this patent is SAMSUNG DISPLAY CO., LTD.. Invention is credited to Junta FUCHIWAKI.
Application Number | 20150179951 14/570394 |
Document ID | / |
Family ID | 53401062 |
Filed Date | 2015-06-25 |
United States Patent
Application |
20150179951 |
Kind Code |
A1 |
FUCHIWAKI; Junta |
June 25, 2015 |
MATERIAL FOR ORGANIC ELECTROLUMINESCENCE DEVICE AND ORGANIC
ELECTROLUMINESCENCE DEVICE USING THE SAME
Abstract
A material for an organic electroluminescence device is
represented by the following Formula 1, ##STR00001## where X.sub.1
to X.sub.7, E, L, Ar.sub.1 and Ar.sub.2 are as defined in the
specification.
Inventors: |
FUCHIWAKI; Junta; (Yokohama,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SAMSUNG DISPLAY CO., LTD. |
Yongin-City |
|
KR |
|
|
Family ID: |
53401062 |
Appl. No.: |
14/570394 |
Filed: |
December 15, 2014 |
Current U.S.
Class: |
257/40 ; 548/440;
549/43; 549/460 |
Current CPC
Class: |
H01L 2251/308 20130101;
H01L 51/0058 20130101; C09K 11/06 20130101; H01L 51/0074 20130101;
H01L 51/0061 20130101; H01L 51/0072 20130101; C07D 307/91 20130101;
H01L 51/0073 20130101; C07D 333/76 20130101; C07D 209/86 20130101;
H01L 51/0081 20130101 |
International
Class: |
H01L 51/00 20060101
H01L051/00; H01L 51/50 20060101 H01L051/50; C07D 209/86 20060101
C07D209/86; C07D 307/91 20060101 C07D307/91; C07D 333/76 20060101
C07D333/76 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 20, 2013 |
JP |
2013-264607 |
Claims
1. A material for an organic electroluminescence (EL) device
represented by the following Formula 1: ##STR00048## where X.sub.1
to X.sub.7 are independently a hydrogen atom, a deuterium atom, a
halogen atom, a substituted or unsubstituted alkyl group having 1
to 15 carbon atoms, a substituted or unsubstituted aryl group
having 6 to 18 ring carbon atoms, or a substituted or unsubstituted
heteroaryl group having 5 to 18 ring carbon atoms, Ar.sub.1 and
Ar.sub.2 are independently a substituted or unsubstituted aryl
group having 6 to 12 ring carbon atoms, or a substituted or
unsubstituted heteroaryl group having 5 to 13 ring carbon atoms, L
is a divalent connecting group represented by the following Formula
2, n is 1 or 2, and E represents an oxygen atom or a sulfur atom,
##STR00049##
2. The material for an organic EL device as claimed in claim 1,
wherein Ar.sub.1 is an aryl group having 6 to 12 ring carbon
atoms.
3. The material for an organic EL device as claimed in claim 1,
wherein E is an oxygen atom.
4. The material for an organic EL device as claimed in claim 1,
wherein Ar.sub.2 is one of the following Groups (3) to (5):
##STR00050##
5. The material for an organic EL device as claimed in claim 1,
wherein each of X.sub.1 to X.sub.7 is substituted with a hydrogen
atom, a fluorine atom, a deuterium atom, an alkyl group having 1 to
15 carbon atoms, or a substituted or unsubstituted aryl group or
fluoroaryl group having 6 to 18 ring carbon atoms.
6. The material for an organic EL device as claimed in claim 1,
wherein the material is one of Compounds (6) to (12): ##STR00051##
##STR00052##
7. An organic electroluminescence (EL) device, comprising a
material for an organic EL device represented by the following
Formula 6: ##STR00053## where X.sub.1 to X.sub.7 are independently
a hydrogen atom, a deuterium atom, a halogen atom, an alkyl group
having 1 to 15 carbon atoms, a substituted or unsubstituted aryl
group having 6 to 18 ring carbon atoms, or a substituted or
unsubstituted heteroaryl group having 5 to 18 ring carbon atoms,
Ar.sub.1 and Ar.sub.2 are independently a substituted or
unsubstituted aryl group having 6 to 12 ring carbon atoms, or a
substituted or unsubstituted heteroaryl group having 5 to 13 ring
carbon atoms, L is a divalent connecting group represented by the
following Formula 2, n is 1 or 2, and E represents an oxygen atom
or a sulfur atom, ##STR00054##
8. The organic EL device as claimed in claim 7, wherein the
material for an organic EL device is included in an emission
layer.
9. The organic EL device as claimed in claim 7, wherein the
material for an organic EL device is included in a layer of stacked
layers located between an emission layer and an anode.
10. The organic EL device as claimed in claim 7, wherein Ar.sub.1
is an aryl group having 6 to 12 ring carbon atoms.
11. The organic EL device as claimed in claim 7, wherein E is an
oxygen atom.
12. The organic EL device as claimed in claim 7, wherein Ar.sub.2
is one of the following Groups (8) to (10): ##STR00055##
13. The organic EL device as claimed in claim 7, wherein each of
X.sub.1 to X.sub.7 is substituted with a hydrogen atom, a fluorine
atom, a deuterium atom, an alkyl group having 1 to 15 carbon atoms,
a substituted or unsubstituted aryl group or fluoroaryl group
having 6 to 18 ring carbon atoms.
14. The organic EL device as claimed in claim 7, wherein the
material for an organic EL device includes one of the following
Compounds 1 to 6: ##STR00056## ##STR00057##
15. The organic EL device as claimed in claim 7, wherein the
material for an organic EL device includes at least one of
Compounds 7 to 18: ##STR00058## ##STR00059## ##STR00060##
##STR00061##
16. The organic EL device as claimed in claim 7, wherein the
material for an organic EL device is at least one of Compounds 19
to 30: ##STR00062## ##STR00063## ##STR00064## ##STR00065##
17. The organic EL device as claimed in claim 7, wherein the
material for an organic EL device is at least one of Compounds 31
to 43: ##STR00066## ##STR00067## ##STR00068## ##STR00069##
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] Japanese Patent Application No. 2013-264607, filed on Dec.
20, 2013, in the Japan Patent Office, and entitled: "Material for
Organic Electroluminescence Device and Organic Electroluminescence
Device Using the Same," is incorporated by reference herein in its
entirety.
BACKGROUND
[0002] 1. Field
[0003] Embodiments relate to a material for an organic
electroluminescence device and an organic electroluminescence
device using the same.
[0004] 2. Description of the Related Art
[0005] In recent years, organic electroluminescence (EL) displays
that are one type of image displays have been actively developed.
Unlike a liquid crystal display and the like, the organic EL
display is so-called a self-luminescent display which recombines
holes and electrons injected from an anode and a cathode in an
emission layer to thus emit lights from a light-emitting material
including an organic compound of the emission layer, thereby
performing display.
[0006] An example of an organic electroluminescence device (organic
EL device) known in the art is an organic EL device which includes
an anode, a hole transport layer disposed on the anode, an emission
layer disposed on the hole transport layer, an electron transport
layer disposed on the emission layer, and a cathode disposed on the
electron transport layer. Holes injected from the anode are
injected into the emission layer via the hole transport layer.
Meanwhile, electrons are injected from the cathode, and then
injected into the emission layer via the electron transport layer.
The holes and the electrons injected into the emission layer are
recombined to generate excitons within the emission layer. The
organic EL device emits light by using lights generated during the
transition of the excitons to a ground state. Also, the organic EL
device is not limited to the above-described configuration but may
be changed in various forms.
SUMMARY
[0007] Embodiments are directed to A material for an organic
electroluminescence (EL) device represented by the following
Formula 1:
##STR00002##
where X.sub.1 to X.sub.7 are independently a hydrogen atom, a
deuterium atom, a halogen atom, a substituted or unsubstituted
alkyl group having 1 to 15 carbon atoms, a substituted or
unsubstituted aryl group having 6 to 18 ring carbon atoms, or a
substituted or unsubstituted heteroaryl group having 5 to 18 ring
carbon atoms, Ar.sup.1 and Ar.sub.2 are independently a substituted
or unsubstituted aryl group having 6 to 12 ring carbon atoms, or a
substituted or unsubstituted heteroaryl group having 5 to 13 ring
carbon atoms, L is a divalent connecting group represented by the
following Formula 2, n is 1 or 2, and E represents an oxygen atom
or a sulfur atom,
##STR00003##
[0008] Ar.sub.1 may be an aryl group having 6 to 12 ring carbon
atoms.
[0009] E may be an oxygen atom.
[0010] Ar.sub.2 may be one of the following Groups (3) to (5):
##STR00004##
[0011] Each of X.sub.1 to X.sub.7 may be substituted with a
hydrogen atom, a fluorine atom, a deuterium atom, an alkyl group
having 1 to 15 carbon atoms, or a substituted or unsubstituted aryl
group or fluoroaryl group having 6 to 18 ring carbon atoms.
[0012] The material may be one of Compounds (6) to (12):
##STR00005## ##STR00006##
[0013] Embodiments are also directed to an organic
electroluminescence (EL) device including a material for an organic
EL device represented by the following Formula 6:
##STR00007##
where X.sub.1 to X.sub.7 are independently a hydrogen atom, a
deuterium atom, a halogen atom, an alkyl group having 1 to 15
carbon atoms, a substituted or unsubstituted aryl group having 6 to
18 ring carbon atoms, or a substituted or unsubstituted heteroaryl
group having 5 to 18 ring carbon atoms, Ar.sub.1 and Ar.sub.2 are
independently a substituted or unsubstituted aryl group having 6 to
12 ring carbon atoms, or a substituted or unsubstituted heteroaryl
group having 5 to 13 ring carbon atoms, L is a divalent connecting
group represented by the following Formula 2, n is 1 or 2, and E
represents an oxygen atom or a sulfur atom,
##STR00008##
[0014] The material for an organic EL device may be included in an
emission layer.
[0015] The material for an organic EL device may be included in a
layer of stacked layers located between an emission layer and an
anode.
[0016] Ar.sub.1 may be an aryl group having 6 to 12 ring carbon
atoms.
[0017] E may be an oxygen atom.
[0018] Ar.sub.2 may be one of the following Groups (8) to (10):
##STR00009##
[0019] Each of X.sub.1 to X.sub.7 may be substituted with a
hydrogen atom, a fluorine atom, a deuterium atom, an alkyl group
having 1 to 15 carbon atoms, a substituted or unsubstituted aryl
group or fluoroaryl group having 6 to 18 ring carbon atoms.
[0020] The material for an organic EL device may include one of the
following Compounds 1 to 6:
##STR00010## ##STR00011##
[0021] The material for an organic EL device may include at least
one of Compounds 7 to 18:
##STR00012## ##STR00013## ##STR00014## ##STR00015##
[0022] The material for an organic EL device may include at least
one of Compounds 19 to 30:
##STR00016## ##STR00017## ##STR00018## ##STR00019##
[0023] The material for an organic EL device may include at least
one of Compounds 31 to 43:
##STR00020## ##STR00021## ##STR00022## ##STR00023##
BRIEF DESCRIPTION OF THE DRAWING
[0024] Features will become apparent to those of skill in the art
by describing in detail exemplary embodiments with reference to the
attached drawing in which:
[0025] FIG. 1 illustrates a schematic diagram of an organic EL
device 100 according to an embodiment.
DETAILED DESCRIPTION
[0026] Example embodiments will now be described more fully
hereinafter with reference to the accompanying drawings; however,
they may be embodied in different forms and should not be construed
as limited to the embodiments set forth herein. Rather, these
embodiments are provided so that this disclosure will be thorough
and complete, and will fully convey exemplary implementations to
those skilled in the art.
[0027] In the drawing figure, the dimensions of layers and regions
may be exaggerated for clarity of illustration.
[0028] A material for an organic EL device according to an
embodiment may include an amine compound combined with a
dibenzofuranyl group or a dibenzothiophenyl group at position 3 via
a phenylene group or a biphenylene group, as represented in the
following Formula 1.
##STR00024##
where E represents an oxygen atom or a sulfur atom. X.sub.1 to
X.sub.7 are independently a hydrogen atom, a deuterium atom, a
halogen atom, a substituted or unsubstituted alkyl group having 1
to 15 carbon atoms, a substituted or unsubstituted aryl group
having 6 to 18 ring carbon atoms, or a substituted or unsubstituted
heteroaryl group having 5 to 18 ring carbon atoms. Preferably, the
halogen atom is fluorine.
[0029] The substituted or unsubstituted alkyl group having 1 to 15
carbon atoms, as a selection for any of X.sub.1 to X.sub.7, may
include a methyl group, an ethyl group, a propyl group, an
isopropyl group, a n-butyl group, a s-butyl group, an isobutyl
group, a t-butyl group, a n-pentyl group, a n-hexyl group, a
n-heptyl group, a n-octyl group, a hydroxymethyl group, a
1-hydroxyethyl group, a 2-hydroxyethyl group, a 2-hydroxyisobutyl
group, a 1,2-dihydroxyethyl group, a 1,3-dihydroxyisopropyl group,
a 2,3-dihydroxy-t-butyl group, a 1,2,3-trihydroxypropyl group, a
chloromethyl group, a 1-chloroethyl group, a 2-chloroethyl group, a
2-chloroisobutyl group, a 1,2-dichloroethyl group, a
1,3-dichloroisopropyl group, a 2,3-dichloro-t-butyl group, a
1,2,3-trichloropropyl group, a bromomethyl group, a 1-bromoethyl
group, a 2-bromoethyl group, a 2-bromoisobutyl group, a
1,2-dibromoethyl group, a 1,3-dibromoisopropyl group, a
2,3-dibromo-t-butyl group, a 1,2,3-tribromopropyl group, an
iodomethyl group, a 1-iodoethyl group, a 2-iodoethyl group, a
2-iodoisobutyl group, a 1,2-diiodoethyl group, a
1,3-diiodoisopropyl group, a 2,3-diiodo-t-butyl group, a
1,2,3-triiodopropyl group, an aminomethyl group, a 1-aminoethyl
group, a 2-aminoethyl group, a 2-aminoisobutyl group, a
1,2-diaminoethyl group, a 1,3-diaminoisopropyl group, a
2,3-diamino-t-butyl group, a 1,2,3-triaminopropyl group, a
cyanomethyl group, a 1-cyanoethyl group, a 2-cyanoethyl group, a
2-cyanoisobutyl group, a 1,2-dicyanoethyl group, a
1,3-dicyanoisopropyl group, a 2,3-dicyano-t-butyl group, a
1,2,3-tricyanopropyl group, a nitromethyl group, a 1-nitroethyl
group, a 2-nitroethyl group, a 2-nitroisobutyl group, a
1,2-dinitroethyl group, a 1,3-dinitroisopropyl group, a
2,3-dinitro-t-butyl group, a 1,2,3-trinitropropyl group, a
cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a
cyclohexyl group, a 4-methylcyclohexyl group, a 1-adamantyl group,
a 2-adamantyl group, a 1-norbornyl group, a 2-norbornyl group,
etc.
[0030] The substituted or unsubstituted aryl group having 6 to 18
ring carbon atoms, as a selection for any of X.sub.1 to X.sub.7,
may include a phenyl group, a biphenylyl group, a 1-naphthyl group,
a 2-naphthyl group, a fluorophenyl group, a difluorophenyl group, a
trifluorophenyl group, a tetrafluorophenyl group, a
pentafluorophenyl group, a toluyl group, a nitrophenyl group, a
cyanophenyl group, a fluorobiphenylyl group, a nitrobiphenylyl
group, a cyanobiphenyl group, a cyanonaphthyl group, a
nitronaphthyl group, a fluoronaphthyl group, a phenanthryl group, a
terphenyl group, a fluoroterphenyl group, etc.
[0031] The substituted or unsubstituted heteroaryl group having 5
to 18 ring carbon atoms, as a selection for any of X.sub.1 to
X.sub.7, may include a dibenzofuranyl group, a dibenzothiophenyl
group, a pyridyl group, a chinolyl group, an isochinolyl group, a
pyrazyl group, a pyrimidinyl group, a triazine group, an imidazolyl
group, an acridinyl group, etc.
[0032] Ar.sub.1 and Ar.sub.2 may independently be a substituted or
unsubstituted aryl group having 6 to 12 ring carbon atoms, or a
substituted or unsubstituted heteroaryl group having 5 to 13 ring
carbon atoms. Substituents of Ar.sub.1 and Ar.sub.2 may include,
for example, a fluoro-group, a chloro-group, an alkyl group having
at most 12 carbon atoms, a fluoroalkyl group having at most 12
carbon atoms, a cycloalkyl group, an acetyl group, an arylester
group, an arylsulfide group, etc.
[0033] The substituted or unsubstituted aryl group having 6 to 12
ring carbon atoms, as a selection for any of Ar.sub.1 and Ar.sub.2,
may include a phenyl group, a biphenylyl group, a 1-naphthyl group,
a 2-naphthyl group, a fluorophenyl group, a difluorophenyl group, a
trifluorophenyl group, a tetrafluorophenyl group, a
pentafluorophenyl group, a toluyl group, a nitrophenyl group, a
cyanophenyl group, a fluorobiphenylyl group, a nitrobiphenylyl
group, a cyanobiphenyl group, a cyanonaphthyl group, a
nitronaphthyl group, a fluoronaphthyl group, etc. For example,
Ar.sub.1 and Ar.sub.2 may be a phenyl group, a biphenylyl group, a
naphthyl group, or a fluorophenyl group. For example, Ar.sub.1 and
Ar2 may be a phenyl group or a biphenylyl group.
[0034] The substituted or unsubstituted heteroaryl group having 5
to 13 ring carbon atoms, as a selection for any of Ar.sub.1 and
Ar.sub.2 may include a dibenzofuranyl group, a dibenzothiophenyl
group, a pyridyl group, a chinolyl group, an isochinolyl group, a
pyrazyl group, a pyrimidinyl group, a triazine group, an imidazolyl
group, an acridinyl group, a carbazolyl group, etc.
[0035] L may be a divalent connecting group represented by the
following Formula 6, where n is 1 or 2.
##STR00025##
[0036] In an embodiment, L may be a phenylene group or a
biphenylene group. The phenylene group or the biphenylene group may
be combined with the nitrogen atom of an amine at a suitable
position.
[0037] In an embodiment, the material for an organic EL device may
be a compound in which E is an oxygen atom, that is, a compound
including a dibenzofuranyl group. The material may be an amine
compound combined with a dibenzofuranyl group with high hole
tolerance and electron tolerance at position 3 via a phenylene
group or a biphenylene group. Long life and high efficiency of an
organic EL device may be realized when compared to an amine
compound making a combination at position 2.
[0038] In an embodiment, Ar.sub.1 in the material for an organic EL
device may be an aryl group having 6 to 12 ring carbon atoms. The
thermal decomposition of a layer of an organic EL device during
forming thereof by a deposition method may be restrained by
limiting the number of the carbon atom for forming a ring of
Ar.sub.1.
[0039] In an embodiment, Ar.sub.2 in the material for an organic EL
device may be represented by one of following groups (8) to
(10):
##STR00026##
[0040] The thermal decomposition of a layer of an organic EL device
during forming thereof by a deposition method may be restrained by
limiting the number of the carbon atom for forming a ring of
Ar.sub.2.
[0041] In an embodiment X.sub.1 to X.sub.7 in the material for an
organic EL device may be a hydrogen atom, a fluorine atom, a
deuterium atom, a substituted or unsubstituted alkyl group having 1
to 15 carbon atoms, a substituted or unsubstituted aryl group or
fluoroaryl group having 6 to 18 ring carbon atoms. The substituted
or unsubstituted aryl group having 6 to 18 ring carbon atoms, as a
selection for any of X.sub.1 to X.sub.7, may include a phenyl
group, a biphenylyl group, a 1-naphthyl group, a 2-naphthyl group,
a fluorophenyl group, a difluorophenyl group, a trifluorophenyl
group, a tetrafluorophenyl group, a pentafluorophenyl group, a
toluyl group, a nitrophenyl group, a cyanophenyl group, a
fluorobiphenylyl group, a nitrobiphenylyl group, a cyanobiphenyl
group, a cyanonaphthyl group, a nitronaphthyl group, a
fluoronaphthyl group, a phenanthryl group, a terphenyl group, a
fluoroterphenyl group, etc. for example, the substituted or
unsubstituted aryl group may be a phenyl group or a biphenylyl
group.
[0042] In the material for an organic EL device, the dibenzofuranyl
group or the dibenzothiophenyl group may be combined with L at the
connecting part of position 3. In a material in which a
dibenzofuranyl group or a dibenzothiophenyl group is combined with
L at position 2, the nitrogen atom of an amine and the oxygen atom
or the sulfur atom of the dibenzofuranyl group or the
dibenzothiophenyl group are disposed at para position. Thus, the
reactivity of radical cations and radical anions may be high, and
the realization of the long life of a device may be difficult.
According to embodiments, the dibenzofuranyl group or the
dibenzothiophenyl group may be combined with the connecting group
at position 3. Accordingly, the stability of the compound with
respect to holes and electrons may be high, and the longer life of
a device may be realized.
[0043] The material for an organic EL device according to
embodiments may be an amine compound combined with the
dibenzofuranyl group or the dibenzothiophenyl group with high hole
tolerance and electron tolerance at position 3 via the phenylene
group or the biphenylene group. A longer life and higher efficiency
of an organic EL device may be realized when compared to a device
using an amine compound making a combination at position 2. In
addition, the thermal decomposition of a layer during forming
thereof by a deposition method may be restrained by controlling the
number of e carbon atoms forming a ring of Ar.sub.1 or
Ar.sub.2.
[0044] The material for an organic EL device according to an
embodiment may be a material illustrated in the following
structures 1 to 6.
##STR00027## ##STR00028##
[0045] The material for an organic EL device according to an
embodiment may be a material illustrated in the following
structures 7 to 12.
##STR00029## ##STR00030##
[0046] The material for an organic EL device according to an
embodiment may be a material illustrated in the following
structures 13 to 18.
##STR00031## ##STR00032##
[0047] The material for an organic EL device according to an
embodiment may be a material illustrated in the following
structures 19 to 24.
##STR00033## ##STR00034##
[0048] The material for an organic EL device according to an
embodiment may be a material illustrated in the following
structures 25 to 30.
##STR00035## ##STR00036##
[0049] The material for an organic EL device according to an
embodiment may be a material illustrated in the following
structures 31 to 36.
##STR00037## ##STR00038##
[0050] The material for an organic EL device according to an
embodiment may be a material illustrated in the following
structures 37 to 43.
##STR00039## ##STR00040##
[0051] The material for an organic EL device according to
embodiments may be appropriately used in an emission layer of an
organic device. In addition, the material for an organic EL device
according to the embodiments may be used in a layer of stacked
layers disposed between the emission layer and an anode. The hole
transporting properties of the organic EL device may be improved,
and the long life and the high efficiency thereof may be
realized.
[0052] (Organic EL Device)
[0053] An organic EL device using the material for an organic EL
device according to embodiments will be explained. FIG. 1 is a
schematic diagram illustrating an organic EL device 100 according
to an embodiment. The organic EL device 100 may include, for
example, a substrate 102, an anode 104, a hole injection layer 106,
a hole transport layer 108, an emission layer 110, an electron
transport layer 112, an electron injection layer 114 and a cathode
116. Suitable materials for each of these may be used. As an
example, the material that was used in each layer in the Examples
and Comparative Examples, below, is provided in FIG. 1. In an
embodiment, the material for an organic EL device according to
embodiments may be used in an emission layer of an organic EL
device. In another embodiment, the material for an organic EL
device may be used in a layer of stacked layers disposed between
the emission layer 110 and the anode 104.
[0054] For example, an embodiment using the material for an organic
EL device in the hole transport layer 108 will be explained. The
substrate 102 may be a transparent glass substrate, a semiconductor
substrate formed by using silicon, etc., or a flexible substrate of
a resin, etc. The anode 104 may be disposed on the substrate 102.
The anode 102 may be formed by using indium tin oxide (ITO), indium
zinc oxide (IZO), etc.
[0055] The hole injection layer 106 My vw disposed on the anode
104. The hole injection layer 106 may include, for example, a
compound of the following Compounds HI1 to HI3.
##STR00041##
[0056] The hole transport layer 108 may be disposed on the hole
injection layer 106. The hole transport layer 108 may be formed
using the material for an organic EL device described above.
[0057] The emission layer 110 may be disposed on the hole transport
layer 108. The emission layer 110 may include a host material
represented by the following Compounds HO1 to HO4, and may be
formed by doping an emission material.
##STR00042##
[0058] As the emission material doped in the emission layer 110,
for example, a compound of the following Compounds DP1 to DP5 may
be used. In addition, the emission material may be doped at an
amount ratio of 0.1 to 50% with respect to a host material.
##STR00043##
[0059] The electron transport layer 112 may be disposed on the
emission layer 110. The electron transport layer 112 may include,
for example, a compound of the following Compounds ET1 to ET4.
##STR00044##
[0060] The electron injection layer 114 may be disposed on the
electron transport layer 112. The electron injection layer 114 may
be formed by using, for example a material including lithium
fluoride (LiF). The cathode 116 may be disposed on the electron
injection layer 114. The cathode may be formed by using a metal
such as Al or a transparent material such as ITO, IZO, etc. The
thin layers may be formed by selecting an appropriate layer forming
method such as vacuum deposition, sputtering, diverse coatings,
etc. according to the materials used.
[0061] In the organic EL device 100 according to an embodiment, a
hole transport layer 108 having high efficiency and long life may
be formed by using the material for an organic EL device. As an
example, the material for an organic EL device may be applied in an
organic EL apparatus of an active matrix type using thin film
transistors (TFT).
[0062] The organic EL device 100 according to an embodiment
includes the material for an organic EL device in an emission layer
or a layer of stacked layers disposed between the emission layer
and an anode. Accordingly, high efficiency and long life of the
organic EL device may be realized.
[0063] The following Examples and Comparative Examples are provided
in order to highlight characteristics of one or more embodiments,
but it will be understood that the Examples and Comparative
Examples are not to be construed as limiting the scope of the
embodiments, nor are the Comparative Examples to be construed as
being outside the scope of the embodiments. Further, it will be
understood that the embodiments are not limited to the particular
details described in the Examples and Comparative Examples.
EXAMPLES
Preparation Method
[0064] The above-described materials for an organic EL device may
be synthesized, for example, by the following methods.
[0065] (Synthesis of Compound 6)
[0066] 4.2 g of 4-bis(biphenylyl)aminophenyl boronic acid pinacol
ester, 2 g of 3-bromodibenzofuran, 0.1 g of
tetrakis(triphenylphosphine)palladium(0), 3.3 g of potassium
carbonate, 180 ml of tetrahydrofuran, and 20 ml of water were added
in a 500 ml, three-necked flask under an argon atmosphere, followed
by heating while refluxing at 80.degree. C. for 12 hours. After
cooling in the air, water was added to the flask, and an organic
layer was separated. The solvent was distilled, and the solid thus
obtained was separated by flash column chromatography to produce
3.6 g of Compound 6 as white solid (yield 80%).
[0067] (Identification of Compound 6)
[0068] The molecular weight of Compound 6 measured by FAB-MS was
563.7.
[0069] Organic EL devices according to Examples 1 to 3 were
manufactured using the above Compounds 2, 6, and 26 as hole
transport materials by the above-described method, and an organic
EL device according to Example 4 was manufactured using Compound 13
as a hole transport material. Compounds 2, 13, and 26 were
synthesized in a similar reaction scheme as described above with
respect to claim 6 by selecting the appropriate starting materials.
In addition, organic EL devices according to Comparative Examples 1
to 5 were manufactured using the following Compounds 51 to 55 as
hole transport materials for comparison. Compounds 51 to 55 are
Comparative Compounds.
##STR00045## ##STR00046## ##STR00047##
[0070] The organic EL devices were formed as stacked layers as
illustrated in FIG. 1. The substrate 102 was formed using a
transparent glass substrate, the anode 104 was formed using ITO to
a thickness of about 150 nm, the hole injection layer 106 was
formed using TNATA (HI1, above) to a thickness of about 60 nm, the
hole transport layer 108 was formed using the compounds of the
examples or the comparative examples to a thickness of about 30 nm,
the emission layer 110 was formed using ADN
(9,10-di(2-naphthyl)anthracene) (HO1, above) doped with 3%
TBP(2,5,8,11-tetra-t-butylperylene) (DP2, above) to a thickness of
about 25 nm, the electron transport layer 112 was formed using
Alg.sub.3 (ET3, above) to a thickness of about 25 nm, the electron
injection layer 114 was formed using LiF to a thickness of about 1
nm, and the cathode 116 was formed using Al to a thickness of about
100 nm.
[0071] With respect to the organic EL devices thus manufactured,
the voltage, the emission efficiency and the life were evaluated.
The evaluation was conducted at the current density of 10
mA/cm.sup.2.
TABLE-US-00001 TABLE 1 Device Emission Life manufacturing Voltage
efficiency LT50 Example Hole transport layer (V) (cd/A) (h) Example
1 Exemplary Compound 2 7.5 8.9 3,800 Example 2 Exemplary Compound 6
8.1 8.7 4,700 Example 3 Exemplary Compound 6.9 9.2 2,200 26 Example
4 Exemplary Compound 6.7 9.0 2,000 13 Comparative Comparative 7.5
5.2 1,800 Example 1 Compound 51 Comparative Comparative 8.1 6.3 900
Example 2 Compound 52 Comparative Comparative 7.6 8.8 1,800 Example
3 Compound 53 Comparative Comparative 7.5 8.3 2,200 Example 4
Compound 54 Comparative Comparative 7.6 8.8 1,600 Example 5
Compound 55
[0072] Referring to the results in Table 1, the organic EL devices
according to Examples 1 to 4 have higher efficiency and longer life
when compared to those according to the comparative examples. When
comparing Example 2 with Comparative Example 2, the organic EL
device using an amine compound combined with a dibenzofuranyl group
at position 3 via a phenylene group in the hole transport layer 108
according to Example 2 has longer life and higher efficiency when
compared to the organic EL device using an amine compound making a
combination at position 2 in the hole transport layer 108 according
to Comparative Example 2, thereby verifying the effects depending
on combining position. Without being bound to theory, it is
believed that in the organic EL device using the amine compound
combined at position 3 in the hole transport layer 108 according to
Example 2, the inflow of electrons from the emission layer 110 may
be restrained. However, in the organic EL device using the amine
compound combined at position 2 in the hole transport layer 108
according to Comparative Example 2, the blocking performance of
electrons may be decreased, and electrons from the emission layer
110 may intrude into the hole transport layer 108. Thus, a decrease
of recombination and deterioration of the hole transport layer 108
may be generated. In addition, when comparing Example 2 and Example
3, the realization of the long life of the organic EL device may be
clearly favorable when introducing the dibenzofuranyl group instead
of the dibenzothiophenyl group. In addition, in the case that
Compound 13 in which heterocyclic structures are introduced as
Ar.sub.1 or Ar.sub.2, was used in the hole transport layer 108, the
effects of a low voltage and high efficiency may be positively
obtained as in Example 4.
[0073] In addition, when Ar.sub.1 and Ar.sub.2 are aryl groups and
when Compound 6 in which Ar.sub.1 and Ar.sub.2 are the biphenylyl
groups as in Example 2, a device having the longest life may be
manufactured. In Comparative Examples 3 to 5, in which substituents
having greater molecular weights than the biphenylyl group as
Ar.sub.1 and Ar.sub.2 are included, the same or better results were
obtained for the voltage, the emission efficiency, etc., however
the lowering of the life was recognized. Without being bound to
theory, adverse effects on the life of the device are considered to
have resulted through the deterioration of sublimation properties
due to the increase of the molecular weight and the increase of a
.pi.-.pi. interaction, and through the generation of impurities by
the partial decomposition of 3-dibenzofuranyl group due to the
increase of a layer manufacturing temperature.
[0074] By way of summation and review, in the application of an
organic EL device in a display apparatus, high efficiency and long
life of the organic EL device are desirable. Particularly, the
emission efficiency and the life of the organic EL device in a blue
emission region may be insufficient when compared to those in a red
emission region or a green emission region. To realize the high
efficiency and the long life of the organic EL device, the
normalization and the stabilization of a hole transport layer have
been examined to realize the high efficiency and the long life of
the organic EL device. Hole transport materials used in the hole
transport layer may generally include a compound including
carbazole or amine or a compound obtained by combining these, such
as a compound including dibenzofuran and an amine. For example, an
amine compound may include fluorene and dibenzofuran or may include
a terphenyl group and dibenzofuran. However, when using a compound
including a terphenyl group or a fluorene ring structure in a
manufacturing process of a layer, thermal decomposition of a
material due to the increase of a depositing temperature may be
generated.
[0075] Other general materials include a polyamine compound
containing dibenzofuran and at least two combined amine parts, an
amine compound containing carbazole and dibenzofuran, a
dibenzofuran derivative, an anthracene derivative containing
dibenzofuran and amine as substituents, a compound in which an
amino group is directly combined with dibenzofuran, dibenzofuran
combined with a substituent containing amine at position 2, a
structure in which 3-dibenzofurane group-phenyl group-amine are
connected in order, an amine derivative containing a deuterated
phenyl group, a monoamine material containing diphenyl or
triphenylated phenyl group and dibenzofuran, a monoamine material
containing a plurality of dibenzofurans combined at position 3, a
monoamine material containing one dibenzofuran combined at a
position other than position 3, as a host material in one emission
layer in an organic EL device including a plurality of emission
layers, and monoamine materials combined with carbazole and
dibenzofuran at position 3.
[0076] However, the organic EL devices using the above-described
materials may have insufficient emission efficiency and emission
life. An organic EL device having higher emission efficiency and
longer life is desirable.
[0077] Embodiments provide a material in which an amine compound is
combined with a dibenzofuranyl group or a dibenzothiophenyl group
at position 3 via a connecting group instead of a general material
in which an amine compound is combined with a dibenzofuranyl group
or a dibenzothiophenyl group at position 2 via a connecting group.
Embodiments provide a material for an organic electroluminescence
device having high efficiency and long life in a blue emission
region, and an organic electroluminescence device using the same.
For example, embodiments provide a material for an organic EL
device having high efficiency and long life and used in an emission
layer or a layer of stacking layers disposed between the emission
layer and an anode, and an organic EL device using the same.
[0078] The long life and the high efficiency of an organic EL
device may be realized by using the material for an organic EL
device according to an embodiment, in which an amine compound is
combined with a dibenzofuranyl group with high hole tolerance and
electron tolerance at position 3 via a phenylene group or a
biphenylene group when compared to a common and widely known
material in which an amine compound makes a combination at position
2. In addition, the thermal decomposition of a layer of the organic
EL device during forming thereof by a deposition method may be
restrained by limiting the number of the atom for forming a ring of
Ar.sub.1 and Ar.sub.2 and the number of the atom of a substituent
at the dibenzofuranyl group.
[0079] In other embodiments, organic EL devices include the
material for an organic EL device described above in an emission
layer.
[0080] In the organic EL device according to an embodiment, longer
life and higher efficiency may be realized by using an amine
compound combined with a dibenzofuranyl group or a
dibenzothiophenyl group with high hole tolerance and electron
tolerance at position 3 via a phenylene group or a biphenylene
group in forming an emission layer when compared to a common amine
compound making a combination at position 2. In addition, the
thermal decomposition of a layer of the organic EL device during
forming thereof by a deposition method may be restrained by
limiting the number of the atom for forming a ring of Ar.sub.1 and
Ar.sub.2.
[0081] In still other embodiments, organic EL devices include the
material for an organic EL device described above in a layer of
stacked layers disposed between an emission layer and an anode.
[0082] In the organic EL device according to an embodiment, long
life and high efficiency may be realized by using an amine compound
combined with a dibenzofuranyl group or a dibenzothiophenyl group
with high hole tolerance and electron tolerance at position 3 via a
phenylene group or a biphenylene group in forming a layer of
stacking layers disposed between an emission layer and an anode. In
addition, the thermal decomposition of a layer of stacked layers
disposed between an emission layer and an anode of the organic EL
device during forming thereof by a deposition method may be
restrained by limiting the number of the atom for forming a ring of
Ar.sub.1 and Ar.sub.2.
[0083] Embodiments provide a material for an organic EL device
having high efficiency and long life and an organic EL device using
the same. A material for an organic EL device having high
efficiency and long life may be used in an emission layer or a
layer of stacking layers disposed between the emission layer and an
anode, and an organic EL device using the same are provided.
[0084] Example embodiments have been disclosed herein, and although
specific terms are employed, they are used and are to be
interpreted in a generic and descriptive sense only and not for
purpose of limitation. In some instances, as would be apparent to
one of ordinary skill in the art as of the filing of the present
application, features, characteristics, and/or elements described
in connection with a particular embodiment may be used singly or in
combination with features, characteristics, and/or elements
described in connection with other embodiments unless otherwise
specifically indicated. Accordingly, it will be understood by those
of skill in the art that various changes in form and details may be
made without departing from the spirit and scope of the present
invention as set forth in the following claims.
* * * * *